AFM Static Test - Results Analysis
04-12-2011, 04:57 PM
#1
AFM Static Test - Results Analysis
Hey guys,
Still diagnosing a pinging / rough idle / just-sort-runs-like-a-turd condition. It's started getting a little worse so I've started checking into more things. Here are the results of my static resistance test on the 7 AFM pins:
Test Target Measured
E2-VS 20-400 1800
E2-VC 100-300 180
E2-VB 200-400 280
E2-THA 2K-3K 2800 (20C)
E1-FC Open Open
So, basically the AFM passes all the tests but the first one, which it fails miserably. Can one of the EFI gurus here please let me know if this seems like a likely culprit? What does the failure mean?
It seems likely that I'll need to replace this AFM. I've heard great things about the Supra AFM swap. However, I figure that if so many people are doing this swap there's got to be alot of good used stock 22re AFM's floating around (hint hint)
Still diagnosing a pinging / rough idle / just-sort-runs-like-a-turd condition. It's started getting a little worse so I've started checking into more things. Here are the results of my static resistance test on the 7 AFM pins:
Test Target Measured
E2-VS 20-400 1800
E2-VC 100-300 180
E2-VB 200-400 280
E2-THA 2K-3K 2800 (20C)
E1-FC Open Open
So, basically the AFM passes all the tests but the first one, which it fails miserably. Can one of the EFI gurus here please let me know if this seems like a likely culprit? What does the failure mean?
It seems likely that I'll need to replace this AFM. I've heard great things about the Supra AFM swap. However, I figure that if so many people are doing this swap there's got to be alot of good used stock 22re AFM's floating around (hint hint)
05-06-2011, 05:10 AM
#3
Registered User
RustBucket - I know this is almost a month late, but I'll post my .02 in case you are still looking at this issue.
If the resistance is linear and it's starting way high, then it seems likely that a high E2-Vs static reading like that would impact your idle and depending on the dynamic reading(s) would also impact all throttle positions. This is the signal that tells the ECU how much air is being sucked in, it's supposed to be at the low end of the range at closed and get higher as the plate opens. Yours appears to read beyond the open range when closed, so if you could do the dynamic test and just slowly move the flapper while looking at the resistance, it might be informative. You may just have a bad spot at closed (static), which seems like that would not matter a whole lot because as long as the engine is running and sucking in some air you would not ever be at that static position. Of course, the whole range could be messed up, but still I would do the dynamic test before I called the AFM bad.
If the resistance is linear and it's starting way high, then it seems likely that a high E2-Vs static reading like that would impact your idle and depending on the dynamic reading(s) would also impact all throttle positions. This is the signal that tells the ECU how much air is being sucked in, it's supposed to be at the low end of the range at closed and get higher as the plate opens. Yours appears to read beyond the open range when closed, so if you could do the dynamic test and just slowly move the flapper while looking at the resistance, it might be informative. You may just have a bad spot at closed (static), which seems like that would not matter a whole lot because as long as the engine is running and sucking in some air you would not ever be at that static position. Of course, the whole range could be messed up, but still I would do the dynamic test before I called the AFM bad.
05-07-2011, 11:24 AM
#4
Registered User
The resistance test on the AFM will just confuse you. It's not linear at all. It stair steps in a zigzag pattern. The way to test it is to apply power and watch the voltage as you move the vane. That should be linear.
Thread
Thread Starter
Forum
Replies
Last Post
clok
General Electrical & Lighting Related Topics
6
11-19-2015 01:09 PM
_Nicco_
86-95 Trucks & 4Runners
35
09-21-2015 03:06 PM
